Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Shoso Tsunekazu

Koji Hashimoto

Kohji Hashimoto

Yuki Iwagami

Akihiro Ishii

Katsuya Nakamoto

Shiro Yonezawa

Susumu Tanaka

Takeshi Kawakami

Shinsuke Suzuki

Koichi Yamane

Daisuke Eguchi

The invention improves safety of an electronic controller using a nonvolatile memory MRAM able to easily perform reading and writing operations at high speed. Therefore, MRAM for writing a control program from an external tool has a correction code adding writing circuit, a decoding reading-out circuit, and error registers for writing an error generating address number thereto as error data. When the error generating address is designated and confirmation reading-out is performed and an error is generated as before, an overlapping abnormality judgment is made and abnormality notification is performed. A program memory area of MRAM is normally in a writing inhibition state. When the external tool is connected, the inhibition state is released. The error registers are arranged in a data memory area set to no writing inhibition object.

Electronic controller

In an vehicle-mounted engine control apparatus according to the present invention, a restart inspection mechanism, which is simpler than an activation inspection mechanism, is provided, and the mechanism to be applied is selected by an initialization determination device. The contents of the restart inspection are limited to malfunction items detected by a periodic code inspector during driving of the vehicle. As a result, the time required to restart a microprocessor when a malfunction occurs is shortened.

Vehicle-mounted engine control apparatus

An in-vehicle electronic control apparatus, having a monitoring control circuit, according to the present invention is configured in such a way that serial interface circuitsandare connected between a main control circuit unitA and a monitoring control circuit unitA, high-speed full-duplex block communication is performed by use of a communication permission signal ALT and a communication synchronization signal CLK, the same question information included in uplink communication information UPD is recurrently transmitted in a plurality times of communication and updated after being transmitted a predetermined times, and the main control circuit unitA returns answer information by use of downlink communication information DND, within a predetermined duration after the update of the question information; because the question update period is prolonged, the control load on the main control circuit unitA is reduced.

In-vehicle electronic control apparatus having monitoring control circuit

First and second on-vehicle electronic control apparatuses which communicate with each other through serial communication interface circuits are fed with powers through an output contact of a power source relay from an on-vehicle battery, an electromagnetic coil of the power source relay is energized through a transistor when a power source switch has been closed, first and second microprocessors are activated upon closure of the output contact, a first watchdog timer generates a self-holding command signal and keeps an operating state of the power source relay when intervals of a watchdog signal which is generated by the first microprocessor are normal, and the self-holding command signal is stopped to deenergize the power source relay, when the first and second on-vehicle electronic control apparatuses have completed their save processing steps in accordance with opening of the power source switch.

Power feed control circuit for on-vehicle electronic control apparatuses

A sensor switchconnected to a constant voltage Vc via a breeder resistorand dropper diodesandis connected to a microprocessorthat configures a wire abnormality detecting device, and the electric potential of the connection point between the dropper diodesandis inputted to the microprocessoras a switch logic signal Dvia a signal wireand a series resistor. The signal voltage level of the switch logic signal Dis inputted to the microprocessorvia an AD converter, and the microprocessorcooperates with a program memoryto perform a determination of whether or not the signal voltage is in an abnormal intermediate voltage state. However, during a transitional period when the switch logic signal is changing between high and low, mistaken determination is prevented by avoiding abnormality determination.

Wire abnormality detecting device

A microprocessor of an on-vehicle electronic control unit controls an on-vehicle current consumer group responsive to input signals of on-vehicle sensor groups based on control program, fixed control constant and semi-fixed control constant respectively stored in first block of a no-volatile memory, and variable control constant having been transferred from second block of the no-volatile memory to RAM memory; and content of RAM memory is learned and compensated during operation. When power supply switch is OFF, contents of the RAM memory are sequentially added to and written in the second block. When the second block is filled up to capacity, batch clear is executed and, thereafter, the latest data is written. Thus, a flash memory divided into the first and second blocks capable of executing batch clear separately is employed as a non-volatile memory, enabling to perform save processing many times with small number of times of batch clear.

On-vehicle electronic control unit

In an electronic control unit, a control constant stored in a program memory is transmitted to a data memory via a serial communication circuit. First control circuit section (master station) and second control circuit section (substation) mutually communicate through series-parallel converters. The master station includes regular transmission device and storage constant confirmation processing device. The substation includes regular report device and confirmation reply device to a data transmitted from the master station. A constant set data transmitted from the master station by regular transmission device is stored in the data memory at the time of normal receiving. Confirmation information such as sum value of the entire data in the data memory is reported by regular report device. At the master station, if there is any error in the confirmation information, a constant set data is retransmitted with regular transmission device. Reliability of data in the data memory is improved.

Growing community of inventors

Chiyoda-ku, Japan

Shoso Tsunekazu